Silly as it sounds, powering down does not do the same job as unplugging the unit. I unplugged the CPU for a while, and it booted up normally thereafter.
I had a loss of power to my XP Home edition Gateway 506GR computer, running with a P IV processor. Since then, the power-up turns on the computer light and the computer fan, but it never boots up. The monitor promptly goes to sleep, like it is receiving no signal. I checked the monitor with another computer, and it is functioning normally. I checked the monitor cable, and it is connected correctly. So, the CPU is not booting up properly. Turning the CPU off/on makes no difference. What do I try next?

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